/*
 * Copyright (C) 2014 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package ux.okhttp3;

import java.nio.charset.Charset;

import javax.annotation.Nullable;

import static ux.okhttp3.internal.Util.ISO_8859_1;

/**
 * An RFC 7617 challenge.
 */
public final class Challenge {
    private final String scheme;
    private final String realm;
    private final Charset charset;

    public Challenge(String scheme, String realm) {
        this(scheme, realm, ISO_8859_1);
    }

    private Challenge(String scheme, String realm, Charset charset) {
        if (scheme == null) throw new NullPointerException("scheme == null");
        if (realm == null) throw new NullPointerException("realm == null");
        if (charset == null) throw new NullPointerException("charset == null");
        this.scheme = scheme;
        this.realm = realm;
        this.charset = charset;
    }

    /**
     * Returns a copy of this charset that expects a credential encoded with {@code charset}.
     */
    public Challenge withCharset(Charset charset) {
        return new Challenge(scheme, realm, charset);
    }

    /**
     * Returns the authentication scheme, like {@code Basic}.
     */
    public String scheme() {
        return scheme;
    }

    /**
     * Returns the protection space.
     */
    public String realm() {
        return realm;
    }

    /**
     * Returns the charset that should be used to encode the credential.
     */
    public Charset charset() {
        return charset;
    }

    @Override
    public boolean equals(@Nullable Object other) {
        return other instanceof Challenge
                && ((Challenge) other).scheme.equals(scheme)
                && ((Challenge) other).realm.equals(realm)
                && ((Challenge) other).charset.equals(charset);
    }

    @Override
    public int hashCode() {
        int result = 29;
        result = 31 * result + realm.hashCode();
        result = 31 * result + scheme.hashCode();
        result = 31 * result + charset.hashCode();
        return result;
    }

    @Override
    public String toString() {
        return scheme
                + " realm=\"" + realm + "\""
                + " charset=\"" + charset + "\"";
    }
}
